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%I #11 Mar 01 2023 15:04:02
%S 1,10,71,474,3103,20190,131204,853176,5555674,36237258,236763125,
%T 1549496420,10156512792,66669881442,438226458380,2884072387268,
%U 19002479773355,125335000366692,827479642104143,5468060901435850
%N Column 1 of triangle A129274; a(n) is the coefficient of q^(n+2) in the squared q-factorial of n+2.
%H Robert Israel, <a href="/A129275/b129275.txt">Table of n, a(n) for n = 0..300</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/q-Factorial.html">q-Factorial</a>.
%F a(n) = [q^(n+2)] Product_{i=1..n+2} { (1-q^i)/(1-q) }^2.
%p P:= (1+q)^2: A[0]:= 1:
%p for n from 1 to 50 do
%p P:= normal(P * (1-q^(n+2))^2/(1-q)^2);
%p A[n]:= coeff(P,q,n+2);
%p od:
%p seq(A[i],i=0..50); # _Robert Israel_, Jun 25 2018
%o (PARI) a(n)=polcoeff(prod(i=1,n+2,(1-x^i)/(1-x))^2,n+2)
%Y Cf. A129274.
%K nonn
%O 0,2
%A _Paul D. Hanna_, Apr 07 2007
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